code: def test_thumbnail_number(test_str):
      # which plot to show as the thumbnail image
      with tempfile.NamedTemporaryFile("w", delete=False) as f:
          f.write("\n".join(['"Docstring"', test_str]))
      try:
          file_conf, blocks = sg.split_code_and_text_blocks(f.name)
      finally:
          os.remove(f.name)
      assert file_conf == {"thumbnail_number": 2}
  
imports: from __future__ import division, absolute_import, print_function, unicode_literals
  import ast
  import codecs
  import copy
  import logging
  import tempfile
  import re
  import os
  import shutil
  import zipfile
  import pytest
  import sphinx_gallery.gen_rst
  from sphinx_gallery import gen_gallery, downloads
  from sphinx_gallery.gen_gallery import generate_dir_rst
  from sphinx_gallery import sphinx_compatibility
  import matplotlib.pyplot
label_desc: Use image node_id 11 for calling a global function with example usage: test_thumbnail_number(test_str) without return types